Flame retardant polymer composition

ABSTRACT

A flame retardant polymer composition having in admixture therewith certain titanates and halogen containing flame retardant additives.

Elited States Patent [191 111 3,855,356 Luce 1 Dec. 17, 1974 FLAMERETARDANT POLYMER COMPOSITION [56] References Cited [75] Inventor: JohnB. Luce, Mount Vernon, Ind. UNITED STATES PATENTS 3 Assignee; GeneralElectric Company, 2,676,927 4/1 954 McCurdy et a1. 260/45.7 pittsfieldMam 3,311,585 3/1967 Edlin "260/297 3,380,847 4/1968 Leoutsacas et a1.117/138 [22] Filed: Oct. 15, 1973 3,686,362 3/1972 Hinckley et a1260/4595 Appl. No.2 406,603

Related Application Data Division of Ser. No. 215,155, Jan. 3, 1972,Pat. No. 3,796,772.

US. Cl...... 260/881, 260/457 R, 260/4575 R,

260/4575 N, 260/4595 G, 260/880 R,

Primary Examiner- V. P. Hoke Attorney, Agent, or Firm-Donald M. Papuga;William F. Mufarri ABSTRACT A flame retardant polymer composition havingin admixture therewith certain titanates and halogen containing flameretardant additives.

2 Claims, N0 Drawings This application is a division of US. Pat.application Ser. No. 215,155, filed Jan. 3, 1972 now US. Pat. No.3,796,772, issued Mar, 12, 1974.

The invention relates to a thermoplastic polymer composition havingexcellent flame retardant properties and more particularly, polymercompositions having in admixture therewith particular titanates.

BACKGROUND OF THE INVENTION It is well known in the art to prepare flameretardant polymer compositions such as flame retardant polycarbonates byemploying halogen substituted bisphenol-A in the preparation thereof.Specifically, US. Pat. No. 3,334,154 discloses such a compositionwherein tetrabromobisphenol-A is employed to prepare a polycarbonatecomposition having excellent flame retardant properties. In addition,other polymers are made flame retardant by adding halogen containingflame retardant additives to such polymers as high impact polystyrenesand acrylonitrile-butadiene-styrene terpolymers. Flame retardantproperties of thermoplastic compositions are extremely high in demand bythe industry as a safety feature requirement. In fact, many applicationsfor thermoplastics carry the requirement that the thermoplastic be flameretardant particularly where they are used by the public or are employedin areas where the public may gather.

With the development and production of supersonic aircraft andother-transportation vehicles wherein there is the need for utmostsafety for passengers being carried therein, there is a great demandthat the materials as supplied therein in the fabrication of suchvehicles be flame retardant or nonflammable. Even though a thermoplasticmay have flame retardant properties, it will, nevertheless, melt anddrip upon exposure to heat.

Such dripping can come intocontact with combustibles I and thereby causeburning of such combustibles. The modes of public transportation beingdeveloped are now using extensive amounts of plastic materials becauseof their high strength to weight ration and because of the estheticproperties that they can impart to the vehicle. Therefore, the addedsafety requirements call for plastic materials to exhibit controlleddripping. Many of the flame retardant compositions exhibit severedripping which is conducive to spreading the even though such polymersmay be classified as flame resistant or flame retardant polymers. I

DESCRIPTION OF THE INVENTION According to this invention, it now beendiscovered that by incorporating with a-flame retardant polymer certaintitanate additives these polymers can'be rendered non ignition ofcombustible material from polymer dripping such as high impactpolystyrene and titanate or nickel titanate or a mixture thereof. Thehalogen containing flame retardant additive may be typically such wellknown materials as hexabromobenzene, hexachlorobenzene,hexabromobiphenyl, hexachlorobiphenyl, decabromobiphenyl,decachlorobiphe- I 2 nyl, decabromobiphenyl ether, decachlorobiphenylether, 2,2-( 3,3 ,5 ,5 '-tetrabromo-4,4 '-dihydroxydiphenyl) propane,2,2-(3,3',5,5-tetrachloro-4,4- dihydroxy-diphenyl) propane, an adduct ofcyclohexane and hexachlorocyclopentadiene (chloran), etc.

The other polymer composition of this invention consists of a styrenepolymer of at least 50 weight percent of styrene having in admixturetherewith 5 to 30 weight percent of a halogen containing flame retardantand 0.01 to about 20 weight percent of nickel titanate. The halogencontaining flame retardant additives employed herein are the same as setforth previously. The styrene polymer may be either a styrenehomopolymer or a styrene copolymer of at least 50 weight percent ofstyrene with the balance being any other monomer copolymerizeable withstyrene monomer. This also includes the high impact polystyrene whichare prepared by poly merizing styrene in the presence of polybutadieneto graft copolymerize the polybutadiene onto the styrene polymer chainthat is formed during polymerization of the styrene monomer. Alsoincluded are the styrenebutadiene block and random copolymers whereinthe butadiene may be present in an amount of from 10-50 weight percentof the styrene polymer.

The halogens employed in all cases are of either the halogen substituteddihydric phenols or the halogen containing flame retardant additives arebromine or chlorine mixtures thereof in the same compound or monomer.

DESCRIPTION OF THE PREFERRED EMBODIMENT The following Example is setforth herein to illustrate in more detail the preferred embodiment; andto illustrate more clearly the principal and practice of this in ventionto those skilled in the art.

EXAMPLE i Eight (8) parts of an acrylonitrile-butadiene-styreneterpolymer (35, 20 and 45 weight percent respectively) is blended with 2parts of hexabromobenzene. Separate blends are then prepared'with 0.5weight percent of percent of calcium tita- TABLE 1.

. Flame Out Additive (Seconds) 0 15 sec? Nickel Titanate l0 sec. CalciumTitanate 10 sec.

Dripping of the polymer occured and ignited cotton underlaymenti"Dripping of the polymer occurred but of the non-flaming type and didnot ignite cotton underlayment As shown in the Example, the addition ofthe particular titanate with the flame retardant-polymer preventedignition of the combustible material around it. It is the combination ofthe titanate with the halogen that offers this effect. Without thetitanate additive, even the so called flame retardant polymers causedburning of combustible material due to dripping polymer.

In the practice of this invention, the other halogen flame retardantadditives set forth previously can be employed in place of thehexabromobenzene used in the Example with essentially the same results.

It will thus be seen that the objects set forth above among those madeapparent from the preceding description are efficiently attained andsince certain changes may be made in carrying out the above process andin the composition set forth without departing from the scope of thisinvention, it is intended that all matters contained in the abovedescription shall be interpreted as illustrative and not ina limitingsense.

matic is styrene.

1. A FLAME RETARDANT POLYMER COMPOSITION COMPRISING IN ADMIXTURE, AVINYL AROMATIC-ACRYLONITRILE-BUTADIENE TERPOLYMER, 5-30 WEIGHT PERCENTOF A HALOGEN CONTAINING FLAME RETARDANT ADDITIVE AND 0.01 TO ABOUT 20.0WEIGHT PERCENT OF A TITANATE SELECTED FROM CALCIUM AND NICKEL TITANATES,AND MIXTURES OF THESE TITANATES; SAID HALOGEN BEING SELECTED FROM THEGROUP CONSISTING OF BROMINE AND CHLORINE.
 2. The composition of claim 1wherein the vinyl aromatic is styrene.